The severe heat wave sweeping Andhra Pradesh for over a fortnight now is the longest and deadliest-ever in the state's history.

For the 20th day in a row on Wednesday, Andhra Pradesh faced severe heat wave conditions that have claimed over 1,209 lives so far.

Chief Minister N Chandrababu Naidu on Tueday wrote to Prime Minister Atal Bihari Vajpayee seeking special assistance from the Union government to pay ex-gratia to the affected families.

Hyderabad Meteorological Centre Director C V V Bhadram agrees the state had not anything like this in a long, long time. "The heat wave set on May 16 and is still continuing without a break. It is quite a long duration," he told rediff.com. 

Bhadram, however, pointed out that temperature-wise the current heat wave is not the worst, though the mercury has hovered around 46 to 48 degrees Celsius at several places.

In the past, the state had recorded temperatures beyond 48 degrees Celsius during peak summer, but the heat waves in 2002, and earlier in 1996 and 1998 had lasted fewer days.

The heat wave in May 2002 had lasted just seven days, but claimed 1,037 lives.   

Heat waves occur when temperatures rise 5 to 6 degrees Celsius above normal and severe heat waves occur when temperatures are 7 to 8 degrees Celsius above normal. Temperatures under 45 degrees Celsius in peak summer are considered normal.

State Relief Commissioner D C Rosaiah told rediff.com that 144 more deaths have been reported since Tuesday evening.

The worst-affected districts include Nalgonda with 192 deaths so far, followed by Guntur 184, West Godavari 175, East Godavari 152, Prakasam 98, Krishna 66, Warangal 50, Chittoor 42, Karimnagar 41, Nellore 31,Visakhapatnam 27 and Khammam and Adilabad 20 each.